Fox Head Ranger MTB Trail Racing Bike Helmet SAFETY - The In-Mold shell works in tandem with a CPSC, CE, AS approved EPS liner, to provide unmatched impact resistance. ADJUSTABLE FIT - The retention system is easily adjusted with one hand so you can achieve the perfect fit on the fly. The adjustable chin straps also ensure the helmet stays secure, even during rough rides. COMFORT - 8 Big Bore vents placed strategically on the helmet provide maximum airflow, as well as keep the helmet lightweight for all day comfort. MTB/TRAIL READY - This is one helmet you can wear everywhere- during leisurely park rides or on hard, adrenaline filled trail rides; this helmet can stand up to whatever you throw at it. PRODUCT SPECIFICATIONS - Available in sizes X-Small/Small, Medium/Large and XL/XXL. XS/S fits 19 3/4" to 21 5/8", M/L fits 21 5/8" to 23 1/4", and XL/XXL fits 23 1/4" to 24 3/4".